硅藻土用作纳米V_2O_5催化剂载体的研究

Study on Property of Diatomite Used as Carrier for Nano-V_2O_5 Catalyst

用煅烧-酸洗的精制工艺处理硅藻土,通过添加助剂,制得适宜浸渍法制备纳米V2O5催化剂的预制载体。研究了酸浓度对硅藻土化学组成的影响,以及焙烧温度和助剂含量对载体强度和吸水性的影响,分别用SEM和ZXF-4自动吸附仪表征硅藻土和载体的微孔结构。结果表明,经过精制处理富集了硅藻壳体,改善硅藻土化学组成和孔结构;温度和硫磺含量对载体性能的影响趋势是相反的,在吸水性和强度二者间应取一个合理的平衡值,适宜的工艺参数为含7.5%的硫磺,焙烧温度850℃,所制备的载体具有合适的孔结构,能很好地满足纳米V2O5活性颗粒进入孔内分散。

Calcinations-acidification process was taken and purified diatomite.The prefab carrier were prepared with adding auxiliary reagent,which is fit for nano-V2O5 catalyst with impregnating.The influence of acid concentration on chemical composition of diatomite was studied.The influences of the baking temperature and the dosage of assistant component on mechanical strength and hydroscopic property of carrier were also studied.The microfinestra structure of diatomite was characterized by SEM and the microporosity of carrier was characterized by ZXF-4 self-adsorptive apparatus.The results showed that the diatomite was enriched and perfected on composition and finestra structure via purifying process.The influence trend of the baking temperature and the dosage of sulfur on the property of the carrier was opposite.It ought to attain reasonable balance value between mechanical strength and absorbency.The feasible technics parameter was 7.5% sulphur and baking temperature within 850℃.The carrier has seemly microfinestra structure,and it is satisfiable commendably for V2O5 particles entering and dispersing in the finestra of carrier.